Flexible display apparatus and method of fabricating the same

ABSTRACT

A method of forming a flexible display apparatus includes: forming a flexible substrate on a support substrate; forming a light-emitting diode on the flexible substrate; forming a first encapsulation layer on the light-emitting diode; forming a second encapsulation layer; bonding the first encapsulation layer to the second encapsulation layer using an adhesive layer between the first encapsulation layer and the second encapsulation layer; separating the support substrate from the flexible substrate and cutting the flexible substrate to form the flexible display apparatus; and forming a polarizing plate on the second encapsulation layer.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/174,776, filed Jun. 6, 2016, which is a continuation of U.S. Pat. No.9,385,331, filed Oct. 30, 2012, which claims priority to and the benefitof Korean Patent Application No. 10-2012-0078959, filed Jul. 19, 2012,the entire content of each of which is incorporated herein by reference.

BACKGROUND 1. Field

Embodiments of the present invention relate to a flexible displayapparatus and a method of fabricating the same.

2. Description of the Related Art

Liquid crystal display devices and organic light-emitting displaydevices which include thin film transistors (TFTs) are widely used indigital cameras, video cameras, or mobile devices such as portablepersonal digital assistants (PDAs) and cellular phones.

Such display devices used in mobile devices are required to be thin,light, and break-resistant. A thin glass substrate may be used to form athin and light display device. In addition, a display device may beprepared using a conventional glass substrate, and then the glasssubstrate may be thinned by a mechanical or chemical method. However,these processes are complicated and difficult to use.

Furthermore, there is a need for a flexible display device that may beapplied to a curved surface so that the mobile devices may have highportability and various shapes. However, conventional glass substratesare not flexible.

In order to overcome this problem, attempts have been made to form alow-temperature polycrystalline silicon thin film transistor on aplastic substrate. A plastic substrate having a thickness of about 0.2mm does not easily break, and has a lower specific gravity than a glasssubstrate. In addition, the weight of the plastic substrate may be ⅕ orless of that of the glass substrate and the plastic substrate may beapplied to a curved surface.

SUMMARY

Aspects of embodiments of the present invention are directed to a thinfilm encapsulation method for efficiently controlling internaloutgassing and blocking infiltration of external moisture in acost-effective manner.

According to an embodiment of the present invention, a method offabricating a flexible display apparatus includes: forming a flexiblesubstrate on a support substrate; forming a light-emitting diode on theflexible substrate; forming a first encapsulation layer on thelight-emitting diode; forming a second encapsulation layer; bonding thefirst encapsulation layer to the second encapsulation layer using anadhesive layer between the first encapsulation layer and the secondencapsulation layer; separating the support substrate from the flexiblesubstrate and cutting the flexible substrate to form the flexibledisplay apparatus; and forming a polarizing plate on the secondencapsulation layer.

The forming of the first encapsulation layer may include forming anorganic-inorganic complex layer on the light-emitting diode.

The forming of the second encapsulation layer may include: forming anorganic-inorganic complex layer on one surface of a base film; andforming an adhesive layer on the organic-inorganic complex layer. Thebase film may be a quarter wave plate, and the organic-inorganic complexlayer may include at least one inorganic layer.

According to another embodiment of the present invention, a method offabricating a flexible display apparatus includes: forming a flexiblesubstrate on a support substrate; forming a light-emitting diode on theflexible substrate; forming a first encapsulation layer on thelight-emitting diode; forming a second encapsulation layer; forming apolarizing plate on the second encapsulation layer; bonding the firstencapsulation layer to the second encapsulation layer using an adhesivelayer between the first encapsulation layer and the second encapsulationlayer; and separating the support substrate from the flexible substrateand cutting the flexible substrate to form the flexible displayapparatus.

The forming of the first encapsulation layer may include forming anorganic-inorganic complex layer on the light-emitting diode.

The forming of the second encapsulation layer may include: forming anorganic-inorganic complex layer on one surface of a base film; andforming an adhesive layer on the organic-inorganic complex layer. Thebase film may be a quarter wave plate. The organic-inorganic complexlayer may include at least one inorganic layer.

According to another embodiment of the present invention, a method offabricating a flexible display apparatus includes: forming a flexiblesubstrate on a support substrate; forming a light-emitting diode on theflexible substrate; forming an encapsulation layer; bonding theencapsulation layer to the light-emitting diode using an adhesive layerbetween the encapsulation layer and the light-emitting diode to seal thelight-emitting diode; separating the support substrate from the flexiblesubstrate and cutting the flexible substrate to form the flexibledisplay apparatus; and forming a polarizing plate on the encapsulationlayer.

The forming of the encapsulation layer may include: forming anorganic-inorganic complex layer on one surface of a base film; andforming an adhesive layer on the organic-inorganic complex layer. Thebase film may be a quarter wave plate. The organic-inorganic complexlayer may include at least one inorganic layer.

According to another embodiment of the present invention, a flexibledisplay apparatus includes: a flexible substrate; a light-emitting diodeon the flexible substrate; a first encapsulation layer on thelight-emitting diode; an adhesive layer on the first encapsulationlayer; a second encapsulation layer on the first encapsulation layer;and a polarizing plate on the second encapsulation layer.

The first encapsulation layer may be an organic-inorganic complex layer.The second encapsulation layer may be an organic-inorganic complex layerthat includes a quarter wave plate and at least one inorganic layer onthe quarter wave plate.

According to another embodiment of the present invention, a flexibledisplay apparatus includes: a flexible substrate; a light-emitting diodeon the flexible substrate; an encapsulation layer on the light-emittingdiode; an adhesive layer between the light-emitting diode and theencapsulation layer; and a polarizing plate on the encapsulation layer.

The encapsulation layer may be an organic-inorganic complex layer thatincludes a quarter wave plate and at least one inorganic layer on thequarter wave plate.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIGS. 1 to 13 are cross-sectional views of a flexible display apparatusaccording to a first embodiment of the present invention;

FIGS. 14 to 16 are cross-sectional views of a flexible display apparatusaccording to a second embodiment of the present invention; and

FIGS. 17 to 19 are cross-sectional views of a flexible display apparatusaccording to a third embodiment of the present invention.

DETAILED DESCRIPTION

Hereinafter, the present invention will be described more fully withreference to the accompanying drawings, in which exemplary embodimentsof the invention are shown. As used herein, the term “and/or” includesany and all combinations of one or more of the associated listed items.Expressions such as “at least one of,” when preceding a list ofelements, modify the entire list of elements and do not necessarilymodify the individual elements of the list.

As the invention allows for various changes and numerous embodiments,particular embodiments will be illustrated in the drawings and describedin detail in the written description. However, this is not intended tolimit the present invention to particular modes of practice, and it isto be appreciated that all changes, equivalents, and substitutes that donot depart from the spirit and technical scope of the present inventionare encompassed in the present invention. In the description of thepresent invention, certain detailed explanations of related art areomitted when it is deemed that they may unnecessarily obscure aspects ofthe invention.

While such terms as “first,” “second,” etc., may be used to describevarious components, such components should not be limited to the aboveterms. The above terms are used to distinguish one component fromanother.

The terms used in the present specification are merely used to describeparticular embodiments, and are not intended to limit the presentinvention. An expression used in the singular encompasses the expressionof the plural, unless it has a clearly different meaning in the context.In the present specification, it is to be understood that the terms suchas “including” or “having,” etc., are intended to indicate the existenceof the features, numbers, steps, actions, components, parts, orcombinations thereof disclosed in the specification, and are notintended to preclude the possibility that one or more other features,numbers, steps, actions, components, parts, or combinations thereof mayexist or may be added.

In the accompanying drawings, thicknesses and sizes of layers or regionsmay be exaggerated for clarity. It will be understood that when aportion such as a layer, membrane, region, and plate, is referred to asbeing “on” another portion, it can be directly on the other portion, orsometimes, intervening portions may also be present therebetween.

Hereinafter, exemplary embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings.

FIGS. 1 to 13 are cross-sectional views of a flexible display apparatusaccording to an embodiment of the present invention to schematicallydescribe a method of fabricating an organic light-emitting displayapparatus.

First, a flexible substrate 111 is formed on a support substrate 101.

The support substrate 101 is separated from the flexible substrate 111by laser beam irradiation, chemical dissolution, or the like which willbe performed in a separation process. The support substrate 101 may be aglass substrate. However, the present invention is not limited thereto.The support substrate 101 may also be, besides the glass substrate,selected from various substrates such as a transparent plastic ormetallic substrate capable of supporting the flexible substrate 111 andenduring processing stress during a process of forming a device and awiring on the flexible substrate 111.

The flexible substrate 111 may have good heat resistance and durability,may be applied to a curved surface, and may be formed of a plasticmaterial with good heat resistance and durability, such as polyethyleneether phthalate, polyethylene naphthalate, polycarbonate, polyarylate,polyetherimide, polyethersulfone, or polyimide. However, the presentinvention is not limited thereto, and various other flexible materialsmay also be used.

Although not shown in FIG. 1, a separation layer (not shown) may beformed between the support substrate 101 and the flexible substrate 111.The separation layer may be formed of various materials, preferably, amaterial suitable for a separation process.

Then, as shown in FIG. 2, a buffer layer 112 may be formed on theflexible substrate 111. The buffer layer 112 may include at least one ofan inorganic layer or an organic layer. The buffer layer 112 plays arole in blocking diffusion of moisture and impurities generated in theflexible substrate 111 and controlling heat transmission during thecrystallization of a semiconductor, resulting in assistingcrystallization of the semiconductor.

Referring to FIG. 3, a thin film transistor (TFT) 120 is formed on thebuffer layer 112. In FIG. 3, a top gate type TFT is illustrated.However, the TFT may be any type of TFT such as a bottom gate type TFT.Hereinafter, the TFT having the structure shown in FIG. 3 will bedescribed.

To form a top gate type transistor, a semiconductor layer 121, a gateinsulating layer 113, a gate electrode 122, an interlayer insulatinglayer 114, a contact hole 124, and source and drain electrodes 123 aresequentially formed on the buffer layer 112.

The semiconductor layer 121 may be formed of polysilicon. In this case,a predetermined region of the semiconductor layer 121 may be doped withimpurities. The semiconductor layer 121 may be formed of amorphoussilicon instead of polysilicon, and may also be formed of variousorganic semiconductor materials such as pentacene.

When the semiconductor layer 121 is formed of polysilicon, amorphoussilicon is formed and crystallized into polysilicon. In order tocrystallize amorphous silicon, rapid thermal annealing (RTA), solidphase crystallization (SPC), excimer laser annealing (ELA),metal-induced crystallization (MIC), metal-induced lateralcrystallization (MILC), or sequential lateral solidification (SLS) maybe used. In order to use the plastic substrate according to the currentembodiment, a method not including a high temperature heating operationmay be desirable.

The gate insulating layer 113 is formed between the semiconductor layer121 and the gate electrode 122 to insulate the gate electrode 122 fromthe semiconductor layer 121. The gate insulating layer 113 may be formedof an insulating material such as silicon oxide or silicon nitride. Thegate insulating layer 113 may also be formed of another insulatingorganic material.

The gate electrode 122 may be formed of a variety of conductivematerials. For example, the gate electrode 122 may be formed of amaterial such as Mg, Al, Ni, Cr, Mo, W, MoW, or Au. In this regard, thegate electrode 122 may have various structures, for example, asingle-layered structure or a multi-layered structure.

The interlayer insulating layer 114 may be formed of an insulatingmaterial such as silicon oxide or silicon nitride. The interlayerinsulating layer 114 may also be formed of another insulating organicmaterial. Portions of the interlayer insulating layer 114 and the gateinsulating layer 113 may be selectively removed to form contact holes124 exposing source and drain regions of the semiconductor layer 121. Inaddition, source and drain electrodes 123 that have a single-layered ormulti-layered structure are formed on the interlayer insulating layer114 using the material used to form the gate electrode 122 (e.g., usinga material suitable for forming the gate electrode 122) so as to fillthe contact holes 124.

Referring to FIG. 4, a planarization layer 115 (protective layer and/orpassivation layer) is formed on the source and drain electrodes 123 soas to protect and planarize the TFT disposed below the planarizationlayer 115. The planarization layer 115 may have various shapes and maybe formed of an organic material such as benzocyclobutene (BCB) or acrylor an inorganic material such as SiNx. The planarization layer 115 mayalso have a single-layered, double-layered, or multi-layered structure,and a variety of modifications may be possible.

Then, an emissive device is formed on the TFT. Although an organiclight-emitting diode (OLED) is used herein as the display device, thepresent invention is not limited thereto, and various display devicesmay also be used.

In order to form the OLED on the TFT, a first electrode 131 is formed onthe planarization layer 115 and is electrically connected to one of thesource and drain electrodes 123 via a contact hole 130 formed in theplanarization layer 115. The first electrode 131 may function as ananode or a cathode and may be formed of various conductive materials.

The first electrode 131 may be a transparent electrode or a reflectiveelectrode according to emission type. The transparent electrode may beformed using ITO, IZO, ZnO, or In₂O₃, and the reflective electrode maybe formed by forming a reflective layer using Ag, Mg, Al, Pt, Pd, Au,Ni, Nd, Ir, Cr, or any combination thereof and forming ITO, IZO, ZnO, orIn₂O₃ on the reflective layer.

Then, referring to FIG. 5, a pixel-defining layer 116 that is patternedusing an insulating material is formed on the first electrode 131 so asto expose at least a portion of the first electrode 131. Thepixel-defining layer 116 may be an inorganic layer formed of aninorganic material selected from silicon oxide (SiO₂), a silicon nitride(SiN_(x)), or the like.

Referring to FIG. 6, an intermediate layer 132, including an emissivelayer (EML), is formed on the exposed portion of first electrode 131through the opening of the pixel-defining layer 116, and a secondelectrode 133 is formed on the intermediate layer 132 to be opposite tothe first electrode 131, so as to prepare the OLED. The intermediatelayer 132 includes at least the EML and may further include at least onelayer selected from a hole injection layer (HIL), a hole transport layer(HTL), an electron transport layer (ETL), or an electron injection layer(EIL).

Referring to FIG. 6, the intermediate layer 132 is patterned tocorrespond to each sub-pixel, i.e., the patterned first electrode 131.However, for convenience of description, FIG. 6 shows one sub-pixel,and, according to another embodiment, the intermediate layer 132 mayalso be formed integrally with the intermediate layer 132 of an adjacentsub-pixel. The intermediate layer 132 may be modified in various forms.For example, the intermediate layer 132 may include a plurality oflayers, wherein one layer thereof may be formed to correspond to eachsub-pixel and the other layers may be formed integrally with theintermediate layer 132 of an adjacent sub-pixel.

If the OLED is a full-color OLED, the EML may be patterned into a redEML, a green EML, and a blue EML according to the red sub-pixel, thegreen sub-pixel, and the blue sub-pixel. In addition, the EML may have amulti-layered structure in which a red EML, a green EML, and a blue EMLare stacked or a single-layered structure including a red emittingmaterial, a green emitting material, and a blue emitting material so asto emit white light.

The second electrode 133 may be a cathode or an anode according to thefunctions of the first electrode 131. The second electrode 133 may alsobe a transparent electrode or a reflective electrode, as the firstelectrode 131. The transparent electrode may include a layer includingLi, Ca, LiF/Ca, LiF/Al, Al, Mg, or any compound thereof, and anauxiliary electrode or bus electrode line may be formed on the layer,and the auxiliary electrode may be formed of a material used to form atransparent electrode, such as ITO, IZO, ZnO, or In₂O₃. In addition, thereflective electrode is formed by blanket depositing Li, Ca, LiF/Ca,LiF/Al, Al, Mg, or any compound thereof.

Referring to FIG. 7, a first encapsulation layer 300 is formed on thesecond electrode 133 to encapsulate the OLED. The first encapsulationlayer 300 may be a first barrier layer of an inorganic material, organicmaterial, or organic-inorganic composite laminate. When the firstencapsulation layer 300 is a multi-layered thin film encapsulation layerin which an inorganic material 300 a and an organic material 300 b arealternately stacked as shown in FIG. 8, the inorganic layer 300 a mayprotect against and block moisture, and the organic layer 300 b mayplanarize and fill defects in the structure. The organic layer 300 b maybe an organic insulating layer that includes one or more commerciallyavailable polymers, e.g., polymethyl methacrylate (PMMA) or polystyrene(PS), a phenol group-based polymer derivative, an acryl-based polymer,an imide-based polymer, an aryl ether-based polymer, an amide-basedpolymer, a fluorinated polymer, a p-xylene-based polymer, a vinylalcohol-based polymer, or any combination thereof. The inorganic layer300 a may be an inorganic insulating layer that includes SiO₂, SiN_(x),SiON, Al₂O₃, TiO₂, Ta₂O₅, HfO₂, ZrO₂, BST, PZT, or the like. The firstencapsulation layer 300 having a multi-layered thin-film structure maybe formed in a thin layer, and may be, for example, a 1.5 dyad film. A 1dyad film includes one inorganic layer and one organic layer, thus, a1.5 dyad film includes one inorganic layer, one organic layer, and thenan additional inorganic layer or organic layer. The stacking order ofthe inorganic layer 300 a and the organic layer 300 b may be modified.Although the first encapsulation layer 300 of FIG. 8 has a complexstructure including one inorganic layer 300 a and one organic layer 300b, the present invention is not limited thereto. The first encapsulationlayer 300 may also have a complex structure including one or moreinorganic layers 300 a and one or more organic layers 300 b.

Then, a second encapsulation layer 500 is separately prepared as shownin FIG. 9.

In a general organic light-emitting display device, an integratedpolarizing film including a polarizing plate and a quarter wave plate isformed on the OLED in order to block a reflection of external light. Inaddition, the OLED includes organic materials and a metallic cathodeincluding Ag, such as Mg:Ag. Properties of the organic materials maydeteriorate or the cathode may be oxidized by moisture or oxygen,resulting in pixel defects, and the like. In order to prevent or reducethe defects, an encapsulation technique using glass may be used, or athin film encapsulation (TFE) technique using an organic layer and aninorganic layer alternately disposed may be used to form a flexibledisplay. In both cases, a water vapor transmission rate (WVTR) requiredto protect the OLED layer from oxygen or moisture may be 10⁻⁶ g/m²/dayor less.

As a plurality of panels are formed on a single substrate in themanufacture of display devices, a separation process for separating asubstrate from a plastic film after the encapsulation process and acutting process for separating each panel from each other needs to beperformed.

When a thin film encapsulation technique is applied, a separatetemporary protective film is adhered onto the thin film encapsulationlayer after the encapsulation process and before the integratedpolarizing film is adhered onto the OLED, and then subsequent processessuch as the separation and cutting processes are conducted, to protectthe lower thin film encapsulation layer from damage which may occur inthe subsequent processes. Then, the temporary protective film isremoved, and the integrated polarizing film is attached thereto.

However, while removing the temporary protective film, defects such astearing of the lower thin film encapsulation layer may occur, andmanufacturing costs may increase due to processes such as adhering andremoving of the temporary protective film. In addition, if amulti-layered organic-inorganic complex layer is formed on the OLED inorder to prevent or reduce infiltration of external moisture, there aremany limitations in the organic material and a process to remove damageof the lower devices. For example, the organic layer needs to besufficiently thick to cover the lower devices. However, it needs to bedeposited as a monomer, and thus a processing difficulty may arise. Inaddition, a large amount of outgas is generated while depositing aninorganic layer due to plasma damage, or the like, thereby causing pixeldefects.

According to the current embodiment, in order to overcome theseproblems, the thickness of the first encapsulation layer 300 isdecreased to be less than that of the existing encapsulation thin film,and the substrate is separated after the second encapsulation layer 500is adhered on the first encapsulation layer 300 on the OLED before theseparation and cutting processes. Thus, the encapsulation process of theOLED may be efficiently conducted in a cost-effective manner.

In order to form the second encapsulation layer 500, a second barrierlayer 513 is formed on a base film 511. The base film 511 is a quarterwave (λ/4) film that changes linearly polarized light to circularlypolarized light, or vice versa, by providing λ/4 phase difference to twopolarization components perpendicular to each other. The second barrierlayer 513 may have a multi-layered structure including at least oneinorganic layer or an inorganic layer 514 and an organic layer 515 whichare alternately stacked as shown in FIG. 10 in a similar manner to thefirst barrier layer of the first encapsulation layer 300. Herein, theinorganic layer 514 may protect against and block moisture, and theorganic layer 515 may perform planarization and defect filling. Theorganic layer 515 may be an organic insulating layer including an acryl,a polyimide, or the like. The inorganic layer 514 may be an inorganicinsulating layer that includes SiO₂, SiN_(x), SiON, Al₂O₃, TiO₂, Ta₂O₅,HfO₂, ZrO₂, BST, PZT, or the like. The stacking order of the inorganiclayer 514 and the organic layer 515 may be changed. Although the secondbarrier layer 513 of FIG. 10 has a complex structure including twoinorganic layers 514 and two organic layers 515, the present inventionis not limited thereto. The second barrier layer 513 may also have acomplex structure including one or more inorganic layers 514 and one ormore organic layers 515.

An adhesive layer 517 is formed on the second barrier layer 513. Theadhesive layer 517 may be formed of an adhesive or glue formed of amaterial that does not alter the optical characteristics of componentsand does not need to be processed at a high temperature while beingcured or dried. For example, an acrylic polymer, a silicon polymer, apolyester, a polyurethane, a polyether, or a synthetic rubber may beused.

Referring to FIG. 11, the second encapsulation layer 500 is disposed onthe first encapsulation layer 300 and bonded thereto using the adhesivelayer 517 by pressurizing the structure (e.g., by applying pressure tothe structure).

By bonding the first encapsulation layer 300 and the secondencapsulation layer 500, the total thickness of the first barrier layerand the second barrier layer 513 may be similar to that of theencapsulation thin film directly formed on the existing OLED. Uponcomparing with existing encapsulation methods of directly forming amulti-layered organic-inorganic complex layer on the OLED, according tothe encapsulation technique of the current embodiment, the secondencapsulation layer 500 is separately formed from the firstencapsulation layer 300 and assembled with the first encapsulation layer300, so that the thickness of the organic layer and the outgas of theinorganic layer may be easily controlled, and infiltration of externalmoisture may be prevented.

Then, as shown in FIG. 12, a delamination process for separating thesupport substrate 101 from the flexible substrate 111 is performed. Thesupport substrate 101 is separated from the flexible substrate 111 bylaser beam irradiation or chemical dissolution. The laser beam may be acoherent light having a wavelength in a range of 100 nm to 350 nm, andmay be, for example, XeCl, KrF, or ArF obtained by combining AF, Kr, Xe,or the like with halogen gas, e.g., F₂, HCl, or the like.

Then, a cutting process of the panel is conducted.

Finally, as shown in FIG. 13, a polarizing plate 519 is formed on thesecond encapsulation layer 500. The polarizing plate 519 may be a linearpolarizing plate or linear polarizing film with a single- ormulti-layered structure. By using the base film 511 that is a λ/4 filmand the polarizing plate 519, the organic light-emitting display devicemay inhibit the reflection of external light.

FIGS. 14 to 16 are cross-sectional views of a flexible display apparatusaccording to another embodiment of the present invention toschematically describe a method of fabricating an organic light emittingdisplay apparatus. The organic light-emitting display apparatusaccording to this embodiment is different from the first embodiment inthat the polarizing plate is disposed on an integrated secondencapsulation layer 500 including a λ/4 plate and organic and inorganicthin films, and the second encapsulation layer 500 is adhered to theOLED. Thus, hereinafter, the descriptions provided above with referenceto FIGS. 1 to 13 may not be repeated.

A TFT 120, an OLED, and a first encapsulation layer 300 are formed onthe flexible substrate 111 formed on the support substrate 101 in thesame manner as described with reference to FIGS. 1 to 8.

Then, a second encapsulation layer 500 is separately prepared as shownin FIG. 14, and a polarizing plate 519 is disposed on the secondencapsulation layer 500.

In order to form the second encapsulation layer 500, a second barrierlayer 513 is formed on one surface of a base film 511. An adhesive layer517 is formed on the second barrier layer 513.

The polarizing plate 519 is disposed on the opposite surface of the basefilm 511. The polarizing plate 519 may be a linear polarizing plate orlinear polarizing film with a single- or multi-layered structure. Byusing the base film 511 that is a λ/4 film and the polarizing plate 519,the organic light-emitting display device may inhibit the reflection ofexternal light.

Referring to FIG. 15, the second encapsulation layer 500 having thepolarizing plate 519 thereon is disposed on the first encapsulationlayer 300 and bonded thereto using the adhesive layer 517 bypressurizing the structure (e.g., by applying pressure to thestructure).

Then, as shown in FIG. 16, a delamination process for separating thesupport substrate 101 from the flexible substrate 111 is performed.Then, a cutting process of the panel is conducted.

FIGS. 17 to 19 are cross-sectional views of a flexible display apparatusaccording to another embodiment of the present invention toschematically describe a method of fabricating an organic light-emittingdisplay apparatus. The organic light-emitting display device accordingto this embodiment is different from the first embodiment in that anorganic-inorganic thin film layer is not formed on a lower substrate andan integrated second encapsulation layer 500 including a λ/4 plate andorganic and inorganic thin films are directly attached to the OLED.Thus, hereinafter, the descriptions provided above with reference toFIGS. 1 to 13 may not be repeated.

A TFT 120 and an OLED are formed on the flexible substrate 111 formed onthe support substrate 101 in the same manner as described with referenceto FIGS. 1 to 6.

Then, as shown in FIG. 9, a second encapsulation layer 500 is separatelyformed. In order to form the second encapsulation layer 500, a secondbarrier layer 513 is formed on a base film 511. An adhesive layer 517 isformed on the second barrier layer 513.

Then, the second encapsulation layer 500 is bonded to the OLED by theadhesive layer 517, as shown in FIG. 17.

Then, as shown in FIG. 18, a delamination process for separating thesupport substrate 101 from the flexible substrate 111 is performed.Then, a cutting process of the panel is conducted.

Then, a polarizing plate 519 is adhered to the second encapsulationlayer 500, as shown in FIG. 19. The polarizing plate 519 may be a linearpolarizing plate or linear polarizing film with a single- ormulti-layered structure. By using the base film 511 that is a λ/4 filmand the polarizing plate 519, the organic light-emitting display devicemay inhibit the reflection of external light to improve contrast.

In the organic light-emitting display apparatus according to one or moreembodiments of the present invention, the OLED may be protected fromexternal oxygen or moisture and damage occurring by attachment anddetachment of a temporary protective film by separating the λ/4 platefrom the polarizing plate and adhering an integrated encapsulationmember including the λ/4 plate and an organic-inorganic thin film to theOLED. Furthermore, by respectively forming the organic-inorganic thinfilm on the OLED and the separate encapsulation layer, processinglimitations that may be caused when a multi-layered organic-inorganiccomplex layer is formed may be eliminated.

As described above, according to the method of fabricating a flexibledisplay apparatus, according to one or more of the above embodiments ofthe present invention, there is provided an encapsulation method bywhich internal outgas may be controlled and infiltration of externalmoisture is inhibited in a cost-effective manner, so that thefabricating may be easily performed and damage to an organiclight-emitting diode may be inhibited.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims andequivalents thereof.

What is claimed is:
 1. A method of manufacturing a flexible displayapparatus comprising: preparing a flexible film on which alight-emitting diode and a first encapsulation layer are sequentiallyformed; preparing a polarizing film on which a second encapsulationlayer and an adhesive layer are sequentially formed; and attaching theflexible film and the polarizing film.
 2. The method of claim 1, whereinthe forming of the first encapsulation layer over the flexible filmcomprises forming a multi-layer barrier layer comprising an inorganiclayer and an organic layer.
 3. The method of claim 1, wherein theforming of the second encapsulation layer over the polarizing filmcomprises forming a multi-layer barrier layer comprising an inorganiclayer and an organic layer.
 4. The method of claim 1, wherein thepreparing of the flexible film comprises separating a support substrateon which the flexible film is formed.
 5. The method of claim 1, whereinthe preparing of the polarizing film comprises attaching a linearpolarizer and a quarter wave polarizer.